Bangs, privacy, and they accept pull requests.
1 - Example, type "!py split" and it'll jump straight to the Python documentation for splitting. "!a MacBook Pro" and it'll jump straight to the MacBook Pro on Amazon. "!w iPhone" and it'll jump straight to the page on the iPhone on Wikipedia. There are thousands of bangs. Do !bangs if you want to see the full list.
2 - They don't track who you are. They don't filter your results based on who you are (************************** is actually BS - because Google shows different people different things, you don't know whether someone else could have actually reached a page via Google.) Even if you're fine with Google having 600 pages worth of information on you, keep in mind that nothing is unhackable. Sooner or later, Google is going to be hacked, or there will be a malicious employee, and those novels of data that they have on you is going to hit the black market. Your SSN, address, high school, birthday, birth town, parents, employer, car, license plate, salary, etc. There's more than enough for someone to call your bank, prove that they're you, and drain your accounts. Duck Duck Go doesn't store your info. Ads are based on your current search topic and nothing more. They don't serve ads to other people, so they won't track you from page to page the way Google will. They won't read your email the way Google will.
3 - Duck Duck Go allows anyone to contribute. I personally added !python27. Other things people have added are "Regex cheat sheet" and "timer".
I really appreciate what you posted in #1 and #3. Up until now I just thought DDG was a simple, privacy-centric search site. I had no idea it offered so much extra functionality.
Now regarding #2... you seem to have a better grasp of what Google has than most people I run into. I'm wondering how much they could have on me, considering I don't use ANY of their 'services'. I used to use their search but that was long ago and many IPs ago. Outside of email and pseudonymous forums my online activity is next to nothing. No loyalty programs, no social nets, no purchasing/discount apps, nothing. My big concern right now is the shadow profile they build based on what contact lists my email address shows up in. I'm already ticked off at every friend and enemy that has offered their contact list up for free to companies like LinkedIn, Facebook, Google, and Twitter. I don't use any of those but based just on the emails I get from LinkedIn ("You just received a request from <name of dipstick> to join them on LinkedIn! Other requests have come from the following people...") I'm thinking all these services have a pretty good idea of my world. Also, my phone number. No one has my address, fortunately. Do you have any observations on this, like what else they might have derived from my activity?